This Article Full Text Full Text (PDF) All Versions of this Article: 135/1/384    most recent pp.103.035527v1 Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via CrossRef Citing Articles via Web of Science (34) Citing Articles via Google Scholar Google Scholar Articles by Lanceras, J. C. Articles by Toojinda, T. Search for Related Content PubMed PubMed Citation Articles by Lanceras, J. C. Articles by Toojinda, T. Agricola Articles by Lanceras, J. C. Articles by Toojinda, T.

ENVIRONMENTAL STRESS AND ADAPTATION

Quantitative Trait Loci Associated with Drought Tolerance at Reproductive Stage in Rice¹

Rice Gene Discovery Unit, BIOTEC (J.C.L.) and Rice Gene Discovery Unit, BIOTEC, National Center for Genetic Engineering and Biotechnology (T.T.), Kasetsart University, Kamphangsaen Campus, Nakhon Pathom, Thailand, 73140; Ubon Rice Research Center, Rice Research Institute, Ubon Rachatani, Thailand (G.P.); and Phrae Rice Research Center, Rice Research Institute, Muang, Phrae, Thailand (B.J.)

Drought is a major constraint to rice (Oryza sativa) yield and its stability in rainfed and poorly irrigated environments. Identifying genomic regions influencing the response of yield and its components to water deficits will aid in our understanding of the genetics of drought tolerance and development of more drought tolerant cultivars. Quantitative trait loci (QTL) for grain yield and its components and other agronomic traits were identified using a subset of 154 doubled haploid lines derived from a cross between two rice cultivars, CT9993-510 to 1-M and IR62266-42 to 6-2. Drought stress treatments were managed by use of a line source sprinkler irrigation system, which provided a linearly decreasing level of irrigation coinciding with the sensitive reproductive growth stages. The research was conducted at the Ubon Rice Research Center, Ubon, Thailand. A total of 77 QTL were identified for grain yield and its components under varying levels of water stress. Out of the total of 77 QTL, the number of QTL per trait were: 7-grain yield (GY); 8-biological yield (BY); 6-harvest index (HI); 5-d to flowering after initiation of irrigation gradient (DFAIG); 10-total spikelet number (TSN); 7-percent spikelet sterility (PSS); 23-panicle number (PN); and 11-plant height (PH). The phenotypic variation explained by individual QTL ranged from 7.5% to 55.7%. Under well-watered conditions, we observed a high genetic association for BY, HI, DFAIG, PSS, TSN, PH, and GY. However, only BY and HI were found to be significantly associated with GY under drought treatments. QTL flanked by markers RG104 to RM231, EMP2_2 to RM127, and G2132 to RZ598 on chromosomes 3, 4, and 8 were associated with GY, HI, DFAIG, BY, PSS, and PN under drought treatments. The aggregate effects of these QTL on chromosomes 3, 4, and 8 resulted in higher grain yield. These QTL will be useful for rainfed rice improvement, and will also contribute to our understanding of the genetic control of GY under drought conditions at the sensitive reproductive stage. Close linkage or pleiotropy may be responsible for the coincidence of QTL detected in this experiment. Digenic interactions between QTL main effects for GY, BY, HI, and PSS were observed under irrigation treatments. Most (but not all) DH lines have the same response in measure of productivity when the intensity of water deficit was increased, but no QTL by irrigation treatment interaction was detected. The identification of genomic regions associated with GY and its components under drought stress will be useful for marker-based approaches to improve GY and its stability for farmers in drought-prone rice environments.

Article, publication date, and citation information can be found at www.plantphysiol.org/cgi/doi/10.1104/pp.103.035527.

^* Corresponding author; e-mail theerayut{at}dna.kps.ku.ac.th; fax 66–034–355196.

Received October 30, 2003; returned for revision January 9, 2004; accepted March 2, 2004.

This article has been cited by other articles:

				M. Maccaferri, M. C. Sanguineti, S. Corneti, J. L. A. Ortega, M. B. Salem, J. Bort, E. DeAmbrogio, L. F. G. del Moral, A. Demontis, A. El-Ahmed, et al. Quantitative Trait Loci for Grain Yield and Adaptation of Durum Wheat (Triticum durum Desf.) Across a Wide Range of Water Availability Genetics, January 1, 2008; 178(1): 489 - 511. [Abstract] [Full Text] [PDF]

				J. Bernier, A. Kumar, V. Ramaiah, D. Spaner, and G. Atlin A Large-Effect QTL for Grain Yield under Reproductive-Stage Drought Stress in Upland Rice Crop Sci., March 1, 2007; 47(2): 507 - 516. [Abstract] [Full Text] [PDF]

				R. Venuprasad, H. R. Lafitte, and G. N. Atlin Response to Direct Selection for Grain Yield under Drought Stress in Rice Crop Sci., February 6, 2007; 47(1): 285 - 293. [Abstract] [Full Text] [PDF]

				L. Xiong, R.-G. Wang, G. Mao, and J. M. Koczan Identification of Drought Tolerance Determinants by Genetic Analysis of Root Response to Drought Stress and Abscisic Acid Plant Physiology, November 1, 2006; 142(3): 1065 - 1074. [Abstract] [Full Text] [PDF]

				K. SHIRASAWA, T. TAKABE, T. TAKABE, and S. KISHITANI Accumulation of Glycinebetaine in Rice Plants that Overexpress Choline Monooxygenase from Spinach and Evaluation of their Tolerance to Abiotic Stress Ann. Bot., September 1, 2006; 98(3): 565 - 571. [Abstract] [Full Text] [PDF]

				B. Yue, W. Xue, L. Xiong, X. Yu, L. Luo, K. Cui, D. Jin, Y. Xing, and Q. Zhang Genetic Basis of Drought Resistance at Reproductive Stage in Rice: Separation of Drought Tolerance From Drought Avoidance Genetics, February 1, 2006; 172(2): 1213 - 1228. [Abstract] [Full Text] [PDF]

				M. M. Chaves and M. M. Oliveira Mechanisms underlying plant resilience to water deficits: prospects for water-saving agriculture J. Exp. Bot., November 1, 2004; 55(407): 2365 - 2384. [Abstract] [Full Text] [PDF]